Another attempt at circumventing the dreaded pinentry-curses

The compile option is just to avoid confusion really.
It doesn't seem to be the fallbacks fault (which primarily checks the
DISPLAY env var).
One reproducible scenario is that we start kube without the
wrappper-script, which ends up starting gpg-agent without the
necessary options, thus finding pinentry-curses in /usr/bin (instead
of what we install ourselves.
We thus now always kill a running gpg-agent first, so we can indeed launch a
new one that has the option set. This fixes at leaset the scenario
above.